Particle Size of Splash Caused by Wave Overtopping at Vertical Breakwaters

In order to clarify the particle size of splash that is caused by wave-overtopping at breakwaters and transported by wind, field observations were conducted at Waku fishing port in Yamaguchi prefecture in the winter season from December 2006 to February 2007. The violent wave run-up at a vertical breakwater and the transportation of splash by wind were recorded by 3 digital video cameras. Wind velocity and wind direction were also measured with an anemometer. The splashes were caught with a kind of Litmus paper which reacts to salt water, and the particle sizes of splashes were analyzed by image processing technique. Based on the observed data, we found explicit formula to determine size distributions of splashed water particles as functions of run-up height and wind velocity.